Convert Raw Scores to Cumulative Percentages
Step 4: Compute the Cumulative Percentage.
Now it is time to compute the cumulative percentage for each raw score (i.e., each X value). Each cumulative percentage gives the percent of individuals at or below its corresponding X value. First, find the sum of f, which is the total number of scores in the population (N). Then find the cumulative percentage by dividing the cumulative frequency (cf) by N. Finally, multiply by 1, or 100%. Here are the formulas.
- C% = cf/N (100%)
- C% = cumulative percentage
- cf = cumulative frequency
- N = total number of scores in the population; N=∑f
Copyright 2005 by the Student Success Center and the University of Houston-Victoria.
Created 2004 by Maranda Koenig. Content Reviewed by Hari Damodaran. Edited by Sandra Heinold.